Burglar-proof safe



2 Sheets-Sheet 1 (No Model.)

G. L. DAMON.-

BURGLAR PROQF SAFE.

Patented Jan. 17,188Z.

(No Model.) 2 Sheets-Sheet 2.

G. L. DAMON.

I BURGLAR PROOF SAFE. No. 252,435. Patented Jan. 17,1882.

h ETERS HmlWLiihogmpher. Wnhingmn, D. c.

citizen of the United States, residing at Bosvents the steel frombeing cal bolts,

UNITED STATES PATENT OFFICEQ,

GEORGE L. DAMON, OF BOSTON, MASSACHUSETTS.

BU RGLAR-PROOF SAFE.

SPECIFICATION forming part of Letters Patent No. 252,435, dated January 17, 1882.

I Application filed October 17, 1881. (No model.)

I ot'large dimensions are now demanded, and up to this titne it has been found impracticable to produce plates of welded steel and iron such I as are required in the manufacture of such To all whom it may concern Be it known that I, GEORGE L. DAMON, a

ton, in the county of Sufl'olk and State of Massachusetts,haveinvented a new and uset'ullm sales, and ot' the thickness named, exceeding provementinBurglar-ProofSates,Vaults,and thirtyinchesinwidthandinshortlengths. Fur- Doors, Prisons, and like Structures, of which thermore,greatdifficultyisexperiencedin hardthe following is a specification. ening plates of this width,

'lhepretlerredmaterialemployedoflateyears the unequal expansion and contraction of the in the construction of,burglar--proot' safes, vaults, doors, and thelike consists of bars and of laminated metal, made of layers of steela-nd iron rolled together, and having a total thickness varying from one-eighth to one fourth of an inch, according to requirement. The advantage of this material is that the layers of steel will harden perfectly drill-proot', and the iron, to which the steel is welded, prefractured and removed in pieces, as would be practicable it solid steel simply were used.

The bars and plates of welded steel. and iron have been built into the class of work named I between layers of plate-iron alternated thus: first, a layer of plateirou; second, a layer of welded steeland iron combined; third, another layer of plate-iron, and then another layer of the combined metal, and so on until a thickness of four or five inches of solid metal is built up, which at this time is deemed neccssar 't'or absolute protection against burglars. In the above construction the several layers have been secured together by rivets, screws, coniand nuts on the inside, and other like means, always cotnmencing at the outside and leaving off on the inside.

In the construction of the above work the layers of combined welded steel and iron have usually been composed of bars, about six to eight inches wide, laid edge to edge, and in some instances the edges or the bars have had rabbets or tongues and grooves, either planed out or formed in the operation of rolling, and notexceedingthree-tburths of an inch in width.

The present mode of using bars or plates of welded steel or iron simply laid together at the edges, as above described, presents a decidedly weak point in construction, as a burglar, by cutting out a piece of iron equal in width to one of the bars can, by making one cut across the bar, bend it and finally break off the bar, and so go on until an entrance is effected.

It musthe borne in mind that safes and vaults two metals in heating and cooling, causing the metal to warp badlyoutot'its desired flatshape. Experience further shows that with plates of great Width the required drill-proof hardness cannot be successfully attained, for the-reason that with bodies of metal of large area the extended surface at the high heat necessary to admit of proper hardening between the metal and the cold waterinto which it is plunged in hardening, thus preventing a sufticiently instantaneous chilling effect from the water to produce a drill-proof hardening of the steel, without which the whole work is a failure; but with narrow bodies of metal the steam escapes as fast as formed, thus permitting the water to act on the surface instantaneously and with the required effect. For these reasons narrow widths of metal are used. It is apparent that ifa safe could be manufactured with the whole thickness of the walls in one or even two layers of welded steel and iron, solidly rolled together, instead of building up the walls of numerous layers, a great improvement would be attained, and equal or protection provided at a less cost of manufacture, the present systctn of fastening the several layers together being dispensed with to a great extent and an important element of weakness in the structure elitninated. In order to secure the result'above specified, so far as may be possible, by securing practieallycontinuouslayers of welded steel and iron, myinventionconsistsintheemploymentot'bars or plates connected at their edges by grooves or laps of sutlicient width to admit of fastening them together firmly by conical bolts, rivets, or other suitable appliances passing through the lapped or grooved joints, as hereinafter described, so as to fasten the pates or sections firmly and securely together.

' ln order that m y invention may be fully understood, I will proceed to describe several modes of carrying it into effect, reference being had to the accompanying drawings, in whichforms a film of steam 2o wrought-iron, interposed between the succesnated plates, according to the present system,

out the construction of a safe, vault, prison. door, or likestructure, which it is important to render proof against drilling and breaking, 70 all the edges are formed and fastened on the principle I have described, by the combination or union of conical rivets or bolts, or equivalent fastenings, with suitable scarfed or tongued joints, and all an gles and corners are strength- 75 curd on the same principle, with such modifications as may be necessitated or rendered desirable by the nature'of the structure. It will be apparent that with my improvement 1 can successfully make a whole safe, 80 vault, or door, using only laminated plates of welded steel and iron, the wrought-iron plates illustrated in Fig. at being wholly dispensed with. vSuch plates have heretofore been used as a re-enforce to compensate, in part, for the 8 weakness caused by the joining of the lami- Figure 1 is a sectional view of two laminated plates connected by a single rabbet or searfed joint with a rivet passing through said joint. Fig. 2 is a similar section of three laminate 5 plates connected by a tongue-and-groove joint with a conical screw-boltpassingthrough said joint. Fig. 3 is a section of two laminated plates connected by an undercut scarf or double rabbet, through'which a conical screw-bolt is to passed as before. Fig. 4. illustrates a mode of applying the invention in the formation of a corner of aburglar-proof safe,with a scarf and I rivet'and-bolt connections on the same principle. I f A and B represent respectively iron and steel portions of laminated plates, which are produced by rolling in the customary manner, already referred to.

G U in Fig. 4. may represent plates of rolled sive layers or courses of laminated steel and bysimple rabbets. I iron plates A B A By my improved construction I can produce Scarfed, rabbeted, or tongucd-and-grooved work wholly of welded steel and iron in bars, 0 joints, in various forms, are shown at E E E. grooved and fastened as shown and described, F represents conical rivets passing through one and one-half inch thick, which will be the scarfed or tongued joints, said rivets being equally as strong and secure against burglars made flush with the respective surfaces of the as work now made of twice the thickness, thus plates, as required on the outer surfaces of the effecting a great saving incest of manufac- 5 safe and on inside surfaces, against which adturc. o .ditioual layers or courses of metal are to be I am aware that it is'not new to construct applied. the walls of burglar-proof safes with alternate F are conical bolts, flush on the outside and plates of iron and steel, and I am also aware receiving nuts G on their inner ends. that conical bolts have been used with alter 100 .These illustrations will serve to enable the nated iron and steel plates. I F J skilled manufacturer to apply myinvention in I am also aware that the walls of burglarall classes of workand under varied requireproof safes constructed of alternate iron and steel plates have been connected at the cor- II ments and circumstances. I do not confine myselftoany dimensions orthickness of metal, ners by scarfed joints. It has been found by 105 repeated experience that the joints, even when scarfed as heretofore,-const1tute a serious elebut recommend metal in bars six to ten inches 40 wide and from one to'three inches in thickness,

ment of weakness, owing to the possibility of cutting and breaking some of the plates and such sizes being now merchantable and admitting of proper hardening. If bent in hardening, I straighten the material by passing bebending the others up from the joints. 1 tween rolls. Neither do. I confine myself to My improvement, which consists in anovel any particular method or style of rivet, bolt, l combination of eonicalbolts with scarfetl joints, or other fastening passing through the joints. as hereinbefore described, adds materially to Rivets, bolts, or whatever form of fastenings the security of the structure by rendering it employed for the purpose have the exposed as impenetrable at the joints asat other parts. [15 ends hardened drill-proof, in order that the Having thus described my invention, the 1 5o workmay be as impenetrable at that point as following is what I claim as new therein and g at any other. desire to secure by Letters Patent:

I do not claim novelty in the simple scar-fed 1. As animprovementin burglar-proof safes,

joints shown in Fig. 1, irrespective of a rivet vaults, doors, and like work, the combination 120 or bolt passingthrongh such scarfed joint, as of rabbet or tongue-and-groove joints, with I am aware that a simple scarf or rabbet of conical bolts or rivets passed through both this form, but of less width, is commonly emmembers of said joints for fastening the same, ployed at the meeting edges of plates used in substantially as described. the construction of safes and like work. v2.. In burglar-proof safes, vaults, or like 12 5 By my mode of combiningrivets or bolts work, the combination of plates put together with the scarfed or tongued joints I provide, with an undercut scarf or double rabbet and in effect, a continuous layer or shell of comconical bolts or rivets passing through both bined hard and tough metal. My improved members of the respective joints, substantially tongued-and-grooved joints (represented in as described.

Figs. 2 and 3) maybe produced by eitherjroll- GEORGE L. DAMON. ing or planing, and may be united by .either Witnesses: I conical rivets or bolts. Under my invention, URIAH A. POLLARD,

wherever thereis welded steel and iron through- ARTHUR B. CURTIS. 

